Furling Line Options

Jan 2, 2017
765
O'Day & Islander 322 & 37 Scottsdale, AZ & Owls Head, ME
My 1/2” Genoa furling line parted yesterday in 28 kt. winds when the Genoa was reefed and therefore under stress. It has a flat section where in wraps around the roller drum so it will fit. That’s where it broke. I checked and you can’t buy a furling line with a flat section. Evidently you extract the core from a regular poly line and the remaining covering serves as the flat part. Unfortunately that reduces the line strength by a half. Not good In my mind.
It occurs to me that I could use an intact slightly thinner dyneema line instead, maybe 3/8”.
Any reason why not?
Thanks.
 
Mar 26, 2011
3,702
Corsair F-24 MK I Deale, MD
a. The line was probably very old. Stripping the core is common practice. You probably do not need to change anything, other than a new line.

b. If it broke at the transition, the taper was probably done incorrectly (normally they break where there is chafe). The core should taper over ~ a 5-10 inches distance.

c. If you change diameter going to Dyneema, make CERTAIN it will fit the existing jammer. It may be too small, requiring you to splice on a cover to make it fatter.

Best wishes!
 
Last edited:

BarryL

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May 21, 2004
1,065
Jeanneau Sun Odyssey 409 Mt. Sinai, NY
Hello,

As mentioned, you certainly can to a smaller diameter line, like 3/8". You just need to be sure that the line will work with whatever kind of cleat, stopper, clutch, jammer you use to hold the line when the sail is furled.

Barry
 
Jan 7, 2014
443
Beneteau 45F5 51551 Port Jefferson
Too thick and it's going to jump the drum. I had that problem. I thinking I'm using 5/16 now maybe 3/8 at most.
 
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Oct 6, 2007
1,132
Hunter H30 1982 Chicago IL
My furler line is 5/16” StaSet for a 150 genoa on 30 foot boat. Larger diameter line would overfill the drum. Flattened 1/2” might fit, but why do that?
 
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Sep 24, 2018
3,372
Catalina 30 MKIII Chicago
To answer the OP's question more directly, Warpspeed has a Dyneema core, although I'm having a tough time pulling the core out of it on my own furling line most likely because I don't have the right tools
 
Sep 24, 2021
386
Beneteau 35s5 Telegraph hrbr Thetis Island
Another options is to strip the cover, and leave the core.. you get the reduction in diameter with less loss of strength (though the issue was probably age/wear rather than weak line originally)
 
Jun 14, 2010
2,331
Robertson & Caine 2017 Leopard 40 CT
To answer the OP's question more directly, Warpspeed has a Dyneema core, although I'm having a tough time pulling the core out of it on my own furling line most likely because I don't have the right tools
:facepalm: I don’t understand this. The cover on a dyneema line is just for handling qualities and sun protection. The strength is from the dyneema core.
 
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Mar 26, 2011
3,702
Corsair F-24 MK I Deale, MD
Another options is to strip the cover, and leave the core.. you get the reduction in diameter with less loss of strength (though the issue was probably age/wear rather than weak line originally)
Yes for stripable Dyneema line, no for polyester (core and cover are both 50% BS, and the core does not wear well).
 
Jun 9, 2008
1,801
- -- -Bayfield
It would be nice to know what kind of furler you have. I sort of think you might have a continuous line that goes around a drum that has an end to end splice in it rather than a line that wraps up around a drum like fishing line in a reel. If so, I can see maybe the 1/2" line is the right size to grip the jaws where it rounds the forestay drum. A Hood 810 LD is such a furler that uses that sort of system. Anyway, it sounds like in time something went to hell and you need to rethread a new line and splice the lines end to end and you will be back in business. I would not use dyneema. It is too slippery to grab in the jaws. Your problem probably is not a week line, but an old line, or the end to end splice wasn't done properly so that it separated.
 
Apr 11, 2020
788
MacGregor 26s Scott's Landing, Grapevine TX
Scrolling through this thread it looks as though the assumption is that Dyneema is the go-to choice in this application. I'm not convinced.

I have limited experience with furlers, but it seems to me the loads are not all that great, so why Dyneema?
at handleable diameters, Dyneema has remarkable strength. It's replacing metal cables in some applications. But in this application it seems like overkill to me.

I found it only a little challenging finding the right line for my furler back in the day: As large as it can be (easy on the hands), how good it grips (easy on the hands), and how resistant it is to UV (unless you plan to stow the furling line after each sail).

It may involve trial and error. It will always involve inspection and maintanence.
 
Jun 14, 2010
2,331
Robertson & Caine 2017 Leopard 40 CT
Scrolling through this thread it looks as though the assumption is that Dyneema is the go-to choice in this application. I'm not convinced.

I have limited experience with furlers, but it seems to me the loads are not all that great, so why Dyneema?
at handleable diameters, Dyneema has remarkable strength. It's replacing metal cables in some applications. But in this application it seems like overkill to me.

I found it only a little challenging finding the right line for my furler back in the day: As large as it can be (easy on the hands), how good it grips (easy on the hands), and how resistant it is to UV (unless you plan to stow the furling line after each sail).

It may involve trial and error. It will always involve inspection and maintanence.
I tend to agree. I use 10mm Dacron braid for my genoa furler (40 ft cat). I see some minor creep when reefed in higher winds, but not enough to make a significant difference on a cruising boat. Perhaps the slight “creep” I observe is more attributable to the wind pulling the sail tighter on the forestay than to furling line stretch.
The other justification for dyneema might be to reduce line diameter if the furling drum isn’t large enough.